Medical conditions such as diabetes require a person afflicted with the condition to regularly self-monitor that person's blood-glucose concentration level. The purpose of monitoring the blood glucose concentration level is to determine the person's blood glucose concentration level and then to take corrective action, based upon whether the level is too high or too low, to bring the level back within a normal range. The failure to take corrective action may have serious medical implications for that person.
One method of monitoring a person's blood glucose level is with a portable testing device. The portable nature of these devices enables users to conveniently test their blood glucose levels at different locations. One type of device utilizes an electrochemical test sensor to harvest the blood sample and to analyze the blood sample. Some electrochemical test sensors include a substrate with electrodes, a dielectric layer, and reagent layers that are screen-printed in succession. A capillary channel for receiving the fluid sample may be formed by affixing a three-dimensional embossed lid, or a spacer and lid on top of it. The dielectric layer in these test sensors defines the area of the electrodes and reagent to be contacted by the blood sample. A defined area is important because the measured current is dependent both on the analyte concentration and the area of the working electrode, which is exposed to the analyte-containing test sample and the reagent layer.
Mass production of electrochemical test sensors is not an inexpensive process. The cost of the process can be decreased by, for example, reducing the number of components or increasing the efficiency of the process itself. Thus, there exists a need for a test sensor that is less costly to produce while still maintaining an accurate measurement of the analyte.
Furthermore, some electrochemical test sensor devices have larger capillary channels than are optimally desirable. The bigger the capillary channel, the more blood from a person is required to fill the channel. Because drawing blood from a person is unpleasant, it would also be desirable to reduce the size of the capillary channel to require less blood, which should reduce the time for taking and testing such a sample. Thus, there also exists a need for a test sensor with a smaller capillary channel.